Body joints or seams of automobiles are currently being sealed by polymeric sealing compositions, usually a vinyl plastisol or epoxy. Nearly every welded seam of an automobile body dictates that the seam be covered with a sealant either before or after the body is primed and painted. These seals are critical because they protect the passenger compartment from moisture, dust and wind or road noise. Seals also prevent leakage and combat corrosion problems. Imperfect of seals lead to quality problems and costly warranty repairs for the manufacturer.
Current commercial seam sealant systems provide beads of sealant material that are applied to completely cover a welded seam or joint in sufficient quantity without marring the appearance of the finished product and contaminating subsequent finishing operations. Recent innovations have provided improved methods and apparatus for applying sealant to a welded seam of an automobile to effectively cover that seam without the use of excessive sealant material. U.S. Pat. No. 4,682,711 has issued to the assignee of this application and is directed to such improved methods and apparatus.
Further improvements are being sought in automotive body sealant methods and apparatus. Seam sealant cost savings, reduced material usage, better seam filling properties, greater adhesive strengths and enhanced seam penetration are also objectives of such efforts.